.TH std::unordered_set::size 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::unordered_set::size \- std::unordered_set::size

.SH Synopsis
   size_type size() const noexcept;  \fI(since C++11)\fP

   Returns the number of elements in the container, i.e. std::distance(begin(), end()).

.SH Parameters

   \fI(none)\fP

.SH Return value

   The number of elements in the container.

.SH Complexity

   Constant.

.SH Example



   The following code uses size to display the number of elements in a
   std::unordered_set<int>:


// Run this code

 #include <iostream>
 #include <unordered_set>

 int main()
 {
     std::unordered_set<int> nums{1, 3, 5, 7};

     std::cout << "nums contains " << nums.size() << " elements.\\n";
 }

.SH Output:

 nums contains 4 elements.

.SH See also

   empty    checks whether the container is empty
            \fI(public member function)\fP
   max_size returns the maximum possible number of elements
            \fI(public member function)\fP
   size
   ssize    returns the size of a container or array
   \fI(C++17)\fP  \fI(function template)\fP
   (C++20)
